Genetic variation between and within populations of Agropyron Gaertn. using RAPD markers

Agropyron species as important range plant species in Iran are resistant to various environmental stresses. This research was conducted to analyze genetic variation in Agropyron desertorum, Ag. Cristatum, Ag. pectiniforume and Ag. elongatum by RAPD markers. Fifty random primers were used and 12 primers were selected, by which, 142 polymorphic bands with lengths ranged from 200 to 3000 bps. Were obtained. On the basis of Nei's gene index, average genetic diversity within populations varied from 0.09 to 0.30. The largest and the smallest values were obtained in population 1550 (from Ag. cristatum; 0.30) and population 225 (from Ag. elongatum; 0.09), respectively. Results showed high variation within populations. Mean of genetic variation within (H_S), Total (H_T) and degree of genetic differentiations (G_ST) were 0.18, 0.34 and 0.47, respectively. Analysis of molecular variance (AMOVA) displayed significant variation within and among Agropyron species and populations. The results showed that only 19.31 present of total variation belong to between species. Between and within populations variations were 22.23 and 58.46 present, respectively. Cluster analysis based on Nei's genetic similarity and UPGMA method, categorized the entries into four clusters. Populations of Ag. Desertorum and Ag. Cristatum grouped in two separate clusters. Populations of Ag. elongatum and Ag. pectiniforme grouped in another cluster and obtained markers could not separate the populations of the two species. One population from Ag. elongatum formed a distinct group.  Classifying the populations using principle coordinate analysis (PCoA), verified the results of cluster analysis. Results showed that enough variation exist between and within Agropyron species and populations that can be used in breeding programs of the species.